Friction gear



Sept'. 20, 1932.

R. ERBAN FRICTION GEAR Filed out :51, 1930 IM'ENTOR. R1 BHHED Ema RN.

A TTORNE) Patented Sept. 20, I932 PATENT "OFFICE RICHARD ERBAN, 0F VIENNA, AUSTBIA FRICTION GEAR Application filed. October 31, 1930, Serial No.

My present invention relates to friction gears of the type in which rolling bodies are interposed between a air of race rings for transmittin torque rom one ring to the other, and as particular reference to improvements in automatic clamping devices. for such gears.

It is known that in gears of-the type mentioned; one or the other of the race rings thereof may, due to its elasticity, be deformed to compensate for "wear on the racerings and on the rolling bodies,'and to produce the necessary operating pressure of the rings capable against the rolling bodies. Moreover, means 1 1 have been provided heretofore to effect deformation of a race ring of a gear of the type mentioned forthe purposes mentioned, but so far as I am aware, no such means heretofore provided has 'proven entirely efficient and satisfactory in use.

The race ring deforming means heretofore provided have consisted, usually, either of systems of levers or-arrangements of cooperating inclined surfaces. Invariably, however, the lever systems heretofore provided have been more or less complicated and therefore unsatisfactory from many different viewpoints, while the inclined surface are rangements have been found to be both difficult and expensive to produce, as well as to satisfactorily embody in a gear. Accordingly, the general object of my present invention is to provide a practical race ring deforming means for friction gears,

which means'is of simple, inexpensive con struction and embodies a minor number of parts which are, compactly arranged and of being readily embodied in a gear, and which is thoroughly reliable and efficient in-operation.

, With the foregoing and other obj cats in view, whichwill become more fully apparent as the nature of my invention is better understood, the same consists in the novel features of construction and in the novel combination and arrangement of parts as will be hereinafter more fully described, illustrated in the accompanying drawing and defined in the appended clalms.

In the drawing, herein like characters of and 492,475, and in Austria November 22, 1929.

reference denote corresponding parts in related views: v

Figure 1 is a view, partlyin elevation and partly in section, of a friction gear embodying race ring deforming means constructed and arranged in accordance with one practical embodiment of my invention.

Figure 2is an enlarged detail view of the lever arrangement shown in Figure 1.

Figure 3 is a view similar to Figure 1 of an alternative embodiment of the invention;

Figure 4is a view similar to Figure 2 of the lever arrangement shown in Figure 3.

Referring first to the embodiment of my invention illustrated in Figures 1 and 2 of the drawing, it will be observed that the friction gear is of a conventional desi includ- 1 and 1", respectively, between which are disposed torque from one to the other of said rings.

According to the embodiment of my invention illustrated in Figures. 1 and 2 of the drawing, the inner race ring 1 constitutes the driving ring and the ring 1 the driven ring,

' the inner ring 1 therefore being adapted to be deformed; i. e., spread or expanded, to compensate for anywear which may occur'on the rolling body engaging faces of the rings, and on the rolling bodies, as well as to pro- .duce the necessary pressure of the rings against the rolling bodies to render the gear efliciently operative.

The driving element of the gear consists in the present instance of a rotatable shaft '13 extending through the inner race ring 1, and in accordance with this embodiment of my invention, the means for deformingor' expanding the ring 1 is interposed between said ring andsaid shaft and consists essentially of a shoe 3 and a cooperating lever 4. The shoe 3 is disposed within the inner racering- 1 and is in-the form of asplit ring neatly fitting said race ring, the end surfaces 6 and 7 of .said shoe, where the same is split asv at 5, being flat and being disposed in outwardly converging spaced relation as shown.

The lever 4 is in the form of a bar of suitmg inner and outer-race rings designated as rolling bodies 2 designedto transmit I,

end formed flat and converged outwardly for cooperation with the end surfaces 6 and 7 of the shoe 3, the said flat, converging side faces of said lever extending, respectively, from the opposite outer end side corners 9 and 11 of the lever inward, respectively, to the points 8 and 10, the lengths of the said converging;

' or inclined faces -of the leverbeing less than flat engagement with said 'end'surfaces 6 and reason of the head 19 of the screw against the rolling bodies.

7 of the shoe. Moreover, saidlever extends normally in a radial direction with respect 'to the shaft 13 and the shoe 3 and the'race rings, and at its inner end is formed with a central,

longitudinal bore into which is threaded an f adjustment screw 18, which latter extends in- .Ward beyond the inner end of the lever and is provided with a spherical head 19 seated in a corresponding recess in the side of the shaft 13. On the shank of the screw 18 is threaded a lock nut 18 for cooperation with the inner end of the lever 4 to secure said screw in any desired position of adjustment. v

It will be obvious from the foregoing, by 18 hearing against the shaft 13, said "screw may be rotatably adjusted relative to the lever 4 to force said lever longitudinally outward, which manifestly will "result in. a wedging action of the converged or inclined side faces of the lever against the end faces 6 and 7 of the shoe 3, with the result of spreading said shoe and thereby'deforming or expending the inner race ring 1. Thus, by means of;

the screw 18, a normal, deforming or expanding tension may be applied to the inner race ring 1 to compensate for wear on therolling body contacting surfaces of the race rings, and on the rolling bodies, as well as to impose any desired normalpressure of the race rings Assuming now that rotation is imparted ,to theshaft 13 in either direction, it is apparent that the inner end portion of the lever 4 will tendto rotate withthe shaft and that, therefore, the outer end portion of the lever will tend to fulcrum at one or the other of its corners 8 or 10 against the related end I face 6 or 7 of the shoe 3, and at its diagonally opposite outer corner 9 or 11 as the case may be, against the other end face of said shoe, with the result of exerting pressure in opposite directions against the end faces of the shoe and effecting furither spreading of said shoe. Consequently, the inner race ring will be spread or expanded automatically upon rotation of the shaft 13 and through the resulting rocking movement of the lever 4 to on the inner end of the lever4 will-be in the direction of the arrow 15. Consequently, by

reason of the resulting tendency} of v the lever to rock, a force in the direction ofjthe arrow 16 will be imposedon the end fa'c'e 6. of the shoe 3 at the corner 8 oftheleye'r, and a force in the direction of the arrow 17 will be imposed on the end face 7 ofthe shoe at the outer corner '11 of the 1ever;;and'since the forces 16 and17 are op ositethere will result a spreading of the shoe. 3 On the other hand, if the direction of rotation'of the shaft 13 is reversed, the action of the lever obviously willbe reversed and spreadin" of .the shoe will be effected by cooperationo the corners 9 and 10 of the lever against the faces 6 and 7, respectively, of the shoe. The arrow 14 indicates the direction of the force acting through the lever in the direction'of the lenfgth thereof to impose the intial aorinormal -de orming tension on the "inner eracevring, which force, due tothe relatively small angle of inclination of the wedging surfaces of the lever and the shoe with-'respecttothe longi-' tudinal axis of the lever, is only a fraction of the spreading forceexerted onkithe shoe. Therefore, the present-structural; arrangement including the adjusting screw 18 arranged as disclosed,-is entirely practicable, it being pointed out in this connection that an angle between 8 and 16 for the'cooperating inclined faces of the shoe and the lever has been found favorable, the exact angle best 3H1 suited to any particular condition depending, of course, upon the materials from which" the shoe and the lever are formed and the coefliecient of; friction between the cooperat-- ing faces ofthese parts.

Referring now to the embodiment of the invention illustrated in Figures 3 and 4 of the drawing, whercin my present automatic ring deformmg means is arranged. to cooperate with the outer race ring of the gear 2.11 1

instead of with the inner race ring thereof, as in the embodiment of my invention illustrated-in Figures land 2 of the drawing, the numeral 20 designates the driving shaft around and in contactwith which are arranged the rolling bodies 2-1 carried by the cage 22, which latter is connected in a well own manner with the driven shaft (not shown). At 23 i designated the outer race ring surrounding the rolling bodies 21 and with the inner face of which said rolling bodies cooperate, while at 24: is designated, generally, the gear casing;

The race ring 23 is split as indicated at 25 and'at each of the two ends thereof formed respectively.

a recessed yoke or by said split is provided with an outwardly directed lug or projection which lugs or projections, designated as52 and 53, respectively, have fiat, outer parallel faces 26 and 27,

At 28 is designatedframe which fits over'the lugs or projections 52, 53 and which has a flat surface defining one end of the recess therein disposed flat against the outer face of one of said lugs. Defining the opposite end of said recess is a face 40 which is inclined outwardly with respect to the end face of said recess first mentioned and which is disposed in spaced relation to the outer face of the other of said lugs, forming with the outer face of the latter lug an outwardly diverging or wedgeshaped recess in which is disposed the inner 2'0 end of the ring deforming lever designated The lever 29 extends normally in a radial direction with respect to the driving shaft and has one side face thereof, at the inner end at least of the lever, formed flat and straight and parallel to the longitudinal axis of the lever,.this face contacting with the inclined surface of the yoke 28. other hand, the opposite side face of the lever, at its inner end, is inclined inwardly in converging relation to the first mentioned side face of the lever, as indicated at 45, so as to contact normally flat against the outer fiat face of the related yoke lug. This inclined face of the lever extends from the point 41 to the related inner 'end corner 42 of the lever, or, in other words, the length of said face 45 is less than the thickness of the yoke 28 and less than the length of the face 27 of the related yoke lug 53. with which it contacts. On the other hand, the yoke 28 is notched from the point 43 outward so that the effective length of the lever surface-which bears against the yoke surface 40; i. e., be-

tween the point 43 and the related end corner 44 of the lever, is approximately equal to the length of the inclined lever face 45.

The outer end 30 of the lever 29 is rounded and seated at the bottom of an inwardly flaring recess formed in the inner end of a plug element 31, which plug element is disposed within a hollow nut 32 in such suitable manner as not to be rotated when said.

nut is rotated. The nut isthreaded into an opening in the gear casing 24 and is provided with a lock nut 33 for cooperation with the gear casing to secure the nut in any desired position of adjustment.

At diametrically opposite points in alinement with the split 25 in the race ring 23, the inner or rolling body engaging face of said ring is eased within the zones designated as 34--35 and 36-37, respectively. That is to say, within said zones the inner face of the race ring deviates sli htly outward from a' 69 true circular path, w ich permits deforma- On thetion-of the race ring by the lever 29 to compensate for wear on the rolling bodies 21 and the related faces of the shaft 20 and the race ring, as well as to permit further deformation of said race ring to impose the desired normal and gear operating pressures ofthe ring against the rolling bodies.

From the foregoing it will be apparent that by rotation of the nut 32, the lever 29 may be forced longitudinally inward, with the obvious consequent result of causing the wedgeshaped inner end portion of said lever to cooperate with the faces 27 and 40 of the lug 53 and the yoke 28, respectively, to impose a contractile deforming pressure upon therace ring 23, thereby to compensate for any wear upon the rolling bodies 21, and upon the cooperaing faces of the shaft 20 and the race ring, as well as to impose anydesired initial or/normal pressure of the race ring and the shaft 20 against the rolling bodies. Assuming, now, that the driving shaft 20 is rotated in one direction or the other, it is apparent that the rolling bodies 21 will tend to revolve with said shaft and therefore will tend to rotate the race ring 23. This obviously will result in tendency of the inner end of the lever 29 to l rotate with said race ring, but since said lever is held at its outer end, the resultwill be that the lever will be rocked, Accordingly, de pending upon the direction of rotation of the race ring 23, the lever will fulcrum at its inner end, either at the points 431, 44 against the face 27 of the lug 53 and against the face 40 of the yoke 28,.respe ctively, or at the points 42 and 43 against said faces 27 and 40, respectively, to, in either event, impose through the lugs 52,53 and the yoke 28,

a contractile deforming pressure upon the race ring to partially or completely take up the play or easement within the zones 3435 and 36-37 of the race ring and thereby impose the desired operating pressure of said ring against the rolling bodies 21.

To better illustrate the action of the lever 29, the arrow 49 in Figure 4 of the drawing indicates the direction of the pressure im-,

posed on said lever by the nut 32, which pressure it will be observed isiin the longitudinal 1 direction of the lever, so that if theangularity of the cooperating wedge surfaces of the lever lever, all of this depending, however, upon the nature of the materials from which the gear is formed and in particular upon the coefficient of friction between the surfaces 27 and and the related lever faces.

Assuming tendency of the race ring 23 to rotate in a counter-clockwise direction according to the showing in the drawing, the arrow -16 in Figure 4- indicates the direction of the resulting force imposed on the outer end of the lever 29. while the arrows 47 and -18 indicate the direction of the race ring deforming forces imposed by the lever upon the lug 53 and the yoke 28, respectively, and transmitted through said yoke and the lugs 52, to the race ring. If the tendency of the race ring should be to rotate in the opposite direction, the force 46 would be in the opposite direction to that shown and the forces at? and 4-8 would be imposed at the points 41 and all, respectively, with the same deforming action as in the first instance upon the race ring. a 7

Although. by inward adjustment of the lever 29 the eliective'length of the face of said lever which contacts with the face' 410 of the yoke 28 is slightly increased, this increase is so slight as to have no appreciable effect upon the operation of the gear. Moreover, by reason of the arrangement shown in Figures 3 and 4c of the drawing. it not only is possible to form the faces 26 and Q7 of the lugs 52 and parallel to one another, but the side faces 1&8 and 39 of the lever 29 may be formed parallel to one another throughout the major portion of the length ofsaid lever, and only one of said side faces need. be inclined to the axis of the lever as, for example, between the points 411 and 4-2. Thus. the incorporation of my improvements in a gear does not involve complicated manufacturing problems nor excessive production costs.

From the foregoing description considered in connection with the accompanying drawing, it is believed that the construction, operation and advantages of my invention will 3 be clearly understood. It is desired to point out, however, that while I have illustrated and herein described certain specific embodiments of my invention, the same is susceptible of various modifications within the spirit and scope of my invention as defined in the appended claims.

movements thereof independently of one am other to effect deformation of said ring, means for longitudinally adjusting said lever, and means whereby operation of said gear effects rocking of said lever.

33. In a friction gear inclusive of rolling bodies and a cooperating race ring, a split shoe within said race ring expansible to spread the latter, said shoe being in the form of a split ring having the end faces thereof where same is split converging outwardly, a drive shaft within said shoe. a lever having a wed geshaped outer end disposed between the converging end faces of said shoe and operatively connected at itsinner end with said drive shaft whereby rotation of the shaft relative to the shoe effects rocking of the lever and expansion of the shoe to deform the ace ring, and means to increase the effective length of said lever to produce a wedging action of the same on the shoe to deform the ring.

4. In a friction gear inclusive of rolling bodies and a cooperating race ring, a split shoe within said race ring expansible to spread the latter, said shoe being in the form of a split ring having the end faces thereof where same is split converging outwardly, a drive shaft within said shoe, a lever having a wedge-shaped outer end disposed between the converging end faces of said shoe, and an operative connection between the inner end of said lever and said shaft whereby rotation of the shaft relative to the shoe effects rocking of the lever and expansion of the shoe to deform the race ring, said connection com.- prising a screw threaded into said lever at itsinner end and seated against said shaft and adjustable to move the lever longitudially thereby to produce a wedgineaction of the lever between the shoe ends to expand the shoe and deform the race ring.

In a friction gear inclusive of rolling bodies and a cooperating race ring adapted to be contracted to compensate for wearand to impose pressure against the rolling bodies. a lever cooperating with said race ring and effective by longitudinal adjustment and by rocking movement thereof independently of one another to contract said ring. means for longitudinally adjusting said lever, and means whereby operation of the gear rocks said lever.

6. In a friction gear inclusive of rolling bodies and a cooperating split race ring, projections on the ends of said ring, a yoke disposed over and engaging one of said projections and spaced from the other of said projections to provide a wedge-shaped recess, an abutment, a lever fulcrumed at one end wedge-shape and against said abutment and having its other end disposed within said recess, means for adjusting said abutment to move the lever longitudinally thereby to produce a wedging action of the same within said recess to contract the race ring, said abutment and said lever being relatively disposed whereby rotation of the race ring produces a rocking movement of the lever to contract the race ring. Y I

7. In a friction gear inclusive of rolling bodies and a cooperating split race ring surrounding said rolling bodies, outward projections on the ends of said race ring, a rel cessed yokedisposed over and engagmg one of said projections, one end face of the recess in said yoke being spaced from the outer face of the other'of said projections and co operating with said face of said lug to provide an inwardly converging recess, an abutment, and a lever fulcrumed at its outer end against saidiabutment and-having arwedges shaped inner end disposed within said recess, said abutment being adjustable to move said lever longitudinally inward, one side face of said lower being straight and parallel with the longitudinal axis of the lever, and a portion of the other side only of said lever being inclined with respect to the longitudinal axis of the lever to impart the aforesaid wedgeshape to the inner end thereof.

8. In afriction gear inclusive of rolling bodies and a cooperating race'ring, race ring deforming means operatively engaged with said race ring and providing a wedge-shaped recess, a lever having a wedge-shape end disposed within said recess, means for longitudinally adjusting said lever to efiect wedging cooperation thereof with said meansthereby to deform the race ring, and means whereby operation of the gear eifects rocking of said lever and consequent cooperation of the same with said means to deform the race ring.

In testimony whereof I afiix m signature.

' RICHARD RBAN. 

